Background: Apnea (APN) and pneumothorax (PTX) are common immediately life-threatening conditions. Ultrasound is a portable tool that captures anatomy and physiology as digital information allowing it to be readily transferred by electronic means. Both APN and PTX are simply ruled out by visualizing respiratory motion at the visceral-parietal pleural interface known as lung sliding (LS), corroborated by either the M-mode or color-power Doppler depiction of LS. We thus assessed how economically and practically this information could be obtained remotely over a cellular network.
Methods: Ultrasound images were obtained on handheld ultrasound machines streamed to a standard free internet service (Skype) using an iPhone. Remote expert sonographers directed remote providers (with variable to no ultrasound experience) to obtain images by viewing the transmitted ultrasound signal and by viewing the remote examiner over a head-mounted webcam. Examinations were conducted between a series of remote sites and a base station. Remote sites included two remote on-mountain sites, a small airplane in flight, and a Calgary household, with base sites located in Pisa, Rome, Philadelphia, and Calgary.
Results: In all lung fields (20/20) on all occasions, LS could easily and quickly be seen. LS was easily corroborated and documented through capture of color-power Doppler and M-mode images. Other ultrasound applications such as the Focused Assessment with Sonography for Trauma examination, vascular anatomy, and a fetal wellness assessment were also demonstrated.
Conclusion: The emergent exclusion of APN-PTX can be immediately accomplished by a remote expert economically linked to almost any responder over cellular networks. Further work should explore the range of other physiologic functions and anatomy that could be so remotely assessed.